A new monitor takes a few hundred milliseconds to write its _.monitor file.
Every viewer that reached a stopped on-demand stream inside that window found
it unwatched and started it again: the later viewer deleted the _.monitor and
_.pid the earlier monitor had just written, each monitor's checkRunning ran
before the other had set its process title, and both launched a producer —
two connections to a source that often allows one, kicking each other off.
The check-and-start in live.php now runs under a per-stream flock
(<id>_.start on the streams tmpfs). The viewers behind the first wait on it,
re-read the monitor pid, and find the stream started. A viewer that dies
releases it with its process. The test runs four simultaneous viewers in
separate processes: one start with the lock, four without.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EuZvjFSdodqgpyXtaoH1Xt
